Bags and methods of bag assembly are disclosed in U.S. Pat. No. 5,782,733 and U.S. Ser. No. 08/896,179, filed Jul. 17, 1997, both of which are herein incorporated by reference. The film material which constitutes the front wall of a typical bag is a biaxially oriented polypropylene, such as a reverse printed biaxially oriented polypropylene, or a cast polypropylene. This material rips or tears in an irregular fashion. Thus, if an openable joint is formed through such front wall, an even and orderly tearing along the joint is not assured.